无法使用haxe.Web.Dispatch进行默认操作

Question

I am currently setting up a website using haxe targetting php and I'm having a problem with the haxe.Web.Dispatch library.

Everything was working well until I tried to implement a doDefault() rule.

I have the following rules in my dispatch api:

doIndex(){ ... }

doPosts(){y:String, m:String, n:String){ ... }

And these will both redirect to the correct webpage. For example these both work fine:

http://foo.com/index
http://foo.com/posts/2013/01/post-title

And now I've implemented

doDefault() {...}

in order to redirect any other urls to a 404 page, but it's not working. Going to the above URLs still works fine but going to

http://foo.com/bar

gives the following error

uncaught exception: DETooManyValues

in file: C:\wamp\www\website\bin\lib\haxe\web\Dispatch.class.php line 191
#0 C:\wamp\www\website\bin\lib\Index.class.php(9): haxe_web_Dispatch->runtimeDispatch(Object(_hx_anonymous))
#1 C:\wamp\www\website\bin\lib\Index.class.php(12): Index->__construct()
#2 C:\wamp\www\website\bin\index.php(9): Index::main()
#3 {main}

The Dispatch documentation says

In case the corresponding method doXXXX is not found on the api object, or if the URL is /, the action doDefault is used instead. An exception DispatchError.DENotFound("XXXX") is thrown if there is no default action (XXXX here being the placeholder for the URL part name).

but it doesn't say anything about the DETooManyValues exception. Anyone have any ideas?

Answer 1

The DETooManyValues error is thrown if the URL you are dispatching has more parts than the matching action.

So if you have:

doPage( name:String );

Then by default "/page/aboutus/" will work, but "/page/aboutus/2/" will not. This applies for doDefault() too - "/" will work, "/bar" will not (by default).

The trick to getting this to work is using a "Dispatch" argument.

doPage( name:String, d:haxe.web.Dispatch ) {
    trace('Get page $name, with other parts: ${d.parts}');
}
doDefault( d:haxe.web.Dispatch ) {
    trace('Get page $name, with other parts: ${d.parts}');
}

If Dispatch knows that your action/method has this dispatch argument, then it assumes your method knows how to deal with the extra values, and will no longer throw the error. You can use the d.parts array to access the extra parts.

Added bonus:

You can also use the d:Disaptch argument to:

// Redirect to a different page, same get/post parameters
d.redirect("/differentpage/", d.params); 

// Redirect to a different controller.  If this is in /doDefault/, the whole URL is passed to the sub-controller.  
// If it is in `doPage` and the URL is /page/some/other/part, only `/some/other/part` will be passed on.
d.dispatch(new SomeOtherController()); 

I have a blog post which explains some more stuff if you're interested:

http://jasononeil.com.au/2013/05/29/creating-complex-url-routing-schemes-with-haxe-web-dispatch/

Also feel free to keep asking questions, always keen to help someone else using Haxe for websites :)